Apparatus for making plate glass



y 22, 19300 F. GELSTHARP APPARATUS FOR MAKING PLATE GLASS Filed Nov. 25, 1927 2 Sheets-Sheet l INVENTOR July 22, 1930. GEL5THARP 1,771,213

APPARATUS FOR MAKING PLATE GLASS Filed Nov. 25, 1927 2 Sheets-Sheet 2 INVENTOR Patented July 22, 1930' UNITED STATES PATENT OFFICE FREDERICK GELST'EABP, OI TARENTUM, PENNSYLVANIA, ASSIGNOB TO PITTSBURGH PLATE GLASS COMPANY, A CORPORATION OF PENNSYLVANIA APPARATUS FOR MAKING PLATE GLASS Application filed November 25, 1927. Serial No. 235,430.

The invention relates to apparatus for producing glass in a continuous sheet or ribbon and involves a further development of the construction shown in my Patent No.

1,615,834. The invention has for its primary objects, the provision of an improved apparatus for accomplishing the function above set forth; the provision of'improved means for permitting the positioning of the rolls relative to the bath, and with them the runway, and for removing the rolls and runway for replacement or repair and to give access to the drawing tank; and the provision of an arrangement designed to give uniformity in temperature conditions on the two sides of the sheet, as it is generated. In the use of the apparatus of said patent, the roll next to the runway exercises a much greater cooling effect than the other roll, due to the greater are of contact between the one roller and the glass than between the other roller and the glass, and the present construction is designed to modify this condition, so that each roller has the same are of contact with the glass and requires the same amount of cooling. Briefly stated, this is accomplished b carrying the sheet straight up to a point a ove the sizing rolls, where it is bent over a third roll while still plastic and then carried on through a leer as in the construction of said patent. One-embodiment of the invention is illustrated in the accompanying drawings, wherein t Figure 1 is a longitudinal vertical section. And Fig. 2 is a section on the line 11-11 of Fig. 1 on a reduced scale.

Referring to the drawings, 1 is a drawing tank or forehearth communicatin with a melting tank 2, which is preferab y of the well-known regenerative type; 3 and 4 are sizing rolls having their peripheries immersed in the glass bath, as shown; 5 is a bending roll over which the glass sheet 6 is turned after it has been drawn upward a short distance above the rollers 3 and 4; 7 is a glass receiving bed or runwa preferably of t e roller type leading into t e roller leer 8; 9 is a truck mounted upon the track 10, and supporting the runway, the sizing rolls and the bending roll; and 11 is a table lying above a plunger mounted in the cylinder 12 carried by the truck for raising the runway 7 and associated parts when'it is desired to move the sheet forming and handling apparatus to one side of the end of the tank.

The truck 9 is provided with a rigid framework in which the rolls 3, 4 and 5 are journaled, as well as the rollers 13, 13, etc. which constitutes the runway. When it is desired to remove the sheet forming apparatus from operative position, fluid is applied to the interior of the cylinder 12 to lift the runway and associated parts, so that the rolls 3 and 4 clear the side walls of the drawing tank, after which the truck is moved along the track 10 to carry the sheet forming apparatus to one side of the end of the tank. In order to steady the framework mounted upon the plunger 11, such framework is guided by means of four posts 14 (Fig. 2) carried upon the corners of the truck. The

lateral movement of the truck is preferably accomplished by means of the screw 15 which extends through a nut 16 carried by the truck, such screw being operated by means of the crank 17 .at the end thereof. The rolls 13 of the runway, and also the rolls 3, 4 and 5 are driven from the main drive shaft 18. This drive shaft operates through the gears 19. to

The roll 5 is driven from this shaft 24 through the intermediary of the bevel gears 25. The roll 4 is driven from the roll 5 by means of the spur pinion '26 (Fig. 1) meshing with spur gears carried by the axles of the rolls 4 and 5. The roll 4 drives the roll 3 through the intermediary of the spur gears 27 and 28 (Fig. 2) carried by the axles of the rolls 4 and 3. The rollers 13 have sprockets at their ends engaged by s rocket chains which pass over such sproc ets and over sprockets carried by the axle of the roll 5.

In this manner, means are provided for driving the rolls 3, 4 and 5 and the rollers 13 when the parts are in any position of vertical or lateral adjustment.

The rolls 3, 4 and 5 are preferably water cooled by means of the pipes 29 secured to suitable swivels 30 at the ends of the axles of the rolls. A cover 30 is preferably provided above the rolls 3, 4 and 5, such cover being movable to and from position by means of the chain 31 secured to an overhead crane. A water cooled gate 32 is shown for cutting off the supply of glass from the melting tank to the drawing tank and for regulating the flow between the tanks, such gate being raised and lowered by any suitable means, not shown.

In operation, the apparatus is positioned, as indicated in Fig. 1, with the rolls 3 and 4 immersed in the glass bath and the driving mechanism is started so as to drive the rolls in the direction indicated in the arrows. The rolls 3 and 4 pick up the glass lying therebetween and feed it upward in the form of a sheet and such sheet can be grasped by any suitable means, the cover 30 at such time being removed, and pulled up over the roll 5 and onto the runway 7 after which the sheet will continue to follow the runway and pass through the leer 8. The operation may also be initiated by the use of a metal bait which is placed between the rolls 3 and 4 before they are lowered into the glass and which is incorporated into the glass sheet after the rolling operation is started. This bait may be connected to any suitable means, which pulls the end of the sheet which is thus started up the roll 5 and around it onto the bed 7, after which the feed of the rolls 3, 4, 5 and 13 will keep the 'sheet moving in the path in which it has been started. The gas burners 33 may or may not be used, depending upon conditions. If the glass is somewhat stiff, as it passes over the roll 5, it may be desirable to use these burners to reheat it slightly. If the glass is sufiiciently plastic, these burners are not required. When it becomes desirable to stop the rolling operation, this is accomplished by applying fluid pressure to the cylinder 12 to lift the rolls 3 and 4 clear of the glass, such rolls being at this time preferably run at a high rate of speed to free the lower end of the glass sheet from the bath. This is readily accomplished, under these conditions, as the tendeffected by the rolls 3 and 4 is preferably of such a degree that the sheet between such rolls and the bending roll 5 is subject to a stretching or elongating action which is negligible in amount, it being undesirable to stretch the sheet at this point, as this elongates any bubbles which may be in the sheet and makes them more apparent in the finished product than they would be if left in a circular form.

What I claim is:

1. In combination, a glass tank containing a body of molten glass and open above a portion of the bath, a pair of horizontal driven sizing rolls above said portion of the bath, at least one of which has its periphery immersed in said body of glass, means for cooling said rolls so as to prevent the glass from sticking thereto, a bending roll located directly above one of said rolls, a glass receiving bed or runway extending laterally from the side of the bending roll, a truck mounted for movement transversely of the line of movement of the glass on the runway, and a lifting device on the truck supporting the runway and rolls and adapted to raise and lower such runway and rolls and to transport them laterally.

2. In combination, a glass tank containing a body of molten glass and open above a portion of the bath, a pair of horizontal driven sizing rolls above said portion of the bath, having their peripheries immersed in said body of glass, means for cooling said rolls to prevent the glass from sticking thereto, a bending roll located directly above one of said rolls, a glass receiving bed or runway extending laterally from the side of the bending roll, a truck mounted for movement transversely of the line of movement of the glass on the runway, and a lifting device on the truck supporting the runway and rolls and adapted to raise and lower such runway and rolls and to transport them laterally.

In testimony whereof, I have hereunto subscribed my name this 18th day of November,

FREDERICK GELSTHARP.

ency of the sheet is to narrow as soon as the rolls 3 and 4 are lifted above the glass. The use of the bending roll 5 in addition to the rolls 3 and 4 permits the sheet 6 to be drawn up straight between the rolls 3 and 4, so that it has, on its two sides, the same amount of contact with the rolls 3 and 4. The glass in the sheet is thus delivered upward from the rolls at a unform temperature on its two sides which is a desirable condition, tending to reduce breakage and promote a satisfactory annealing operation. The cooling operation as 

